Because of their relatively small size and form, mobile electronic devices such as personal navigation devices (PNDs), smart phones, mobile phones, personal digital assistants (PDAs), watches, and so forth, offer several practical advantages with respect to providing maps and map-related content to a user. For example, because of their portability, mobile electronic devices are capable of providing real time navigational information to a user in a convenient fashion, such as while the user is traveling.
Some navigation activities may be undertaken with respect to certain events of nature, such as sunrise and sunset. Events of nature can depend on local conditions such as latitude, elevation, and/or topology, which can affect a local time of occurrence. Outside physical activities, such as walking, running, hiking, biking, and other modes of transportation may preferably be performed under favorable visibility conditions, such as with sufficient daylight. Some activities, such as driving, flying, and/or marine travel, may be subject to various rules and/or laws that reference a position of the sun, such as by referring to periods of day or night. For example, some vision-impaired drivers may be restricted to only operating a vehicle during daylight hours, a plane or boat may not be equipped with the required lighting for night operations, or changing tides may make traveling a particular nautical route unwise.